Scalable Room‐Temperature Synthesis of Mesoporous Nanocrystalline ZnMn₂O₄ with Enhanced Lithium Storage Properties for Lithium‐Ion Batteries

Abstract

In this work, we put forward a facile yet efficient room-temperature synthetic methodology for the smart fabrication of mesoporous nanocrystalline ZnMn2O4 in macro-quality from the birnessite-type MnO2 phase. A plausible reduction/ion exchange/re-crystallization mechanism is tentatively proposed herein for the scalable synthesis of the spinel phase ZnMn2O4. When utilized as a high-performance anode for advanced Li-ion battery (LIB) application, the as-synthesized nanocrystalline ZnMn2O4 delivered an excellent discharge capacity of approximately 1288 mAh g(-1) on the first cycle at a current density of 400 mA g(-1), and exhibited an outstanding cycling durability, rate capability, and coulombic efficiency, benefiting from its mesoporous and nanoscale structure, which strongly highlighted its great potential in next-generation LIBs. Furthermore, the strategy developed here is very simple and of great importance for large-scale industrial production.

Chemically Integrated Multiwalled Carbon Nanotubes/Zinc Manganate Nanocrystals as Ultralong-Life Anode Materials for Lithium-Ion Batteries

“…39 The intensive peak at 0.20 V ascribes to the reduction of Mn 2+ and Zn 2+ to Mn 0 and Zn 0 , which is embedded in a Li 2 O matrix, followed by the formation of the Li−Zn alloy. 20,26 During the subsequent oxidation process, the broad peak at about 1.35 V could be closely associated with the reactions of Mn to MnO and Zn to ZnO along with the decomposition of Li 2 O matrix. 22 In the second cycle, the intense reduction peak shifts to 0.4 V, due to the reduction of MnO and ZnO.…”

“…39−41 Such a process can be confirmed by controlled experiments, in which only ZnMn 2 O 4 microspheres with an average diameter of 1 μm could be produced under the same synthesis conditions in the absence of moMWCNT ( Figure S2). It is postulated that 26 The existence of C, Zn, Mn and O elements in MZMO2 is proved by the STEM images (Figure 3a,b) and elemental mapping analyses (Figure 3c−f), in which the successful grafting of ZnMn 2 O 4 nanocrystals on MWCNT is experimentally mapped out. Figure 4a demonstrates the typical X-ray diffraction (XRD) pattern of the MZMO2.…”

“…26 Figure 4e depicts the high-resolution spectra of O 1s, which have been splitted into two different valence states. The peak located at 529.9 eV corresponds to the metal−oxygen bonds, 26 while the peak at 531.5 eV is attributed to CO and CO. 33 From the peak areas of the XPS spectra, the Mn/Zn atomic ratio is 1.87 in the MZMO2, close to the stoichiometry of the ZnMn 2 O 4 .…”

Crumpled ZnMn2O4 Nanosheets for Long‐Term‐Cycling Lithium‐Ion Battery Anodes

“…Usually, ternary transition metal oxides have shown better performance than single metal oxides due to their possible synergetic enhancement . Hence, nanostructured ZnMn 2 O 4 has been investigated to improve the electrochemical performance for LIBs …”

Achieving High‐Performance Supercapacitors by Constructing Porous Zinc–Manganese Oxide Microstructures

“…Zinc-manganese oxide (ZnMn 2 O 4 )h as raised much attention because of its wide application in the fields of catalysts,s olid electrolytes,n egative temperature coefficient thermistors,a nd sensor materials.I n ZnMn 2 O 4 ,t he bivalent Zn 2 + ions occupyt he tetrahedral sites and the trivalent Mn 3 + ions the octahedral sites in the spinel structure,a nd it has been proposed as am ore intriguing alternative anode material for advanced lithium-ion batteries (LIBs), benefiting from the low oxidationp otentials (i.e., delithiation potential) of zinc and manganesea t1 .2 and 1.5 V( vs.L i + /Li), respectively. [16][17][18][19][20][21] However, there are very few reports of the micro/nanostructured ZnMn 2 O 4 for SC applications.[22]Herein, we have successfully synthesized porous ZnMn 2 O 4 microstructures by calcinationo fa no xalate precursor under different temperatures.W eh ave not used any templateo r surfactanta nd chose an oxalate precursor (the mixture of zinc-manganese oxalates), which showsl ow cost,g ood structural stability,a nd ar elatively low decompositiont emperature.M ore importantly,t he electrochemical measurements show that the porousZ nMn 2 O 4 microstructure exhibits good electrochemical capacitor behavior.Thes cheme of the synthesis is showni nF igure 1. Firstly, the mixture of Zn-Mno xalates can be obtained by co-precipitation using ammonium oxalate and mixture of manganese acetate and zinc nitrate.S econdly,t he plate-like precursors were calcined at different temperaturesi na ir, and then powders of porous ZnMn 2 O 4 microstructures can be easily obtained.…”